From 1b4f926c07d97be365621e52628c637cfa3772f3 Mon Sep 17 00:00:00 2001
From: Fredrik Johansson <fredrik.johansson@gmail.com>
Date: Sat, 1 Jun 2024 18:58:48 +0200
Subject: [PATCH] test dlog_rho

---
 src/dlog/rho.c          |  5 +++++
 src/dlog/test/t-dlog.c  | 19 ++++++++++++++-----
 src/dlog/test/t-modpe.c |  2 +-
 src/dlog/test/t-vec.c   |  2 +-
 4 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/src/dlog/rho.c b/src/dlog/rho.c
index 2e0a714bf6..d2ad05c8cd 100644
--- a/src/dlog/rho.c
+++ b/src/dlog/rho.c
@@ -76,6 +76,10 @@ dlog_rho(const dlog_rho_t t, ulong b)
 
     flint_rand_init(state);
 
+    /* Fixme: the general algorithm hangs */
+    if (t->mod.n <= 3)
+        return dlog_single(b, t->a, t->mod, t->n.n);
+
     do {
 
         for (k = 0; k < RWALK; k++)
@@ -116,3 +120,4 @@ dlog_rho(const dlog_rho_t t, ulong b)
     else
         return nmod_div(e[0], f[0], t->n);
 }
+
diff --git a/src/dlog/test/t-dlog.c b/src/dlog/test/t-dlog.c
index 4b127c539c..bfef5b38f8 100644
--- a/src/dlog/test/t-dlog.c
+++ b/src/dlog/test/t-dlog.c
@@ -17,11 +17,12 @@ TEST_FUNCTION_START(dlog, state)
 {
     slong iter;
 
-    for (iter = 0; iter < 1000; iter++)
+    for (iter = 0; iter < 100 * flint_test_multiplier(); iter++)
     {
         dlog_table_t table;
         dlog_bsgs_t bsgs;
         dlog_crt_t crt;
+        dlog_rho_t rho;
         dlog_precomp_t pre1, pre100;
         ulong p, a, k;
         nmod_t modp;
@@ -37,12 +38,13 @@ TEST_FUNCTION_START(dlog, state)
         dlog_table_init(table, a, p);
         dlog_bsgs_init(bsgs, a, p, p-1, dlog_bsgs_size(p, 1));
         dlog_crt_init(crt, a, p, p-1, 10);
+        dlog_rho_init(rho, a, p, p-1);
         dlog_precomp_n_init(pre1, a, p, p-1, 1);
         dlog_precomp_n_init(pre100, a, p, p-1, 100);
 
         for (k = 1; k < 100 && k < p; k++)
         {
-            ulong l0, l1, l2, l3, l4, l5;
+            ulong l0, l1, l2, l3, l4, l5, l6;
 
             l1 = dlog_table(table, k);
             l2 = dlog_bsgs(bsgs, k);
@@ -50,22 +52,29 @@ TEST_FUNCTION_START(dlog, state)
             l4 = dlog_precomp(pre1, k);
             l5 = dlog_precomp(pre100, k);
 
+            /* rho is slow, so don't test every time */
+            if (n_randint(state, 10) == 0)
+                l6 = dlog_rho(rho, k);
+            else
+                l6 = l5;
+
             if (iter < 50 && k <= 7)
                 l0 = dlog_once(k, a, modp, p-1);
             else
                 l0 = l1;
 
-            if (l0 != l1 || l1 != l2 || l1 != l3 || l1 != l4 || l1 != l5)
+            if (l0 != l1 || l1 != l2 || l1 != l3 || l1 != l4 || l1 != l5 || l1 != l6)
             {
                 flint_printf("\n\nFAIL: log(%wu,%wu) mod %wu\n\n",k,a,p);
-                flint_printf("once: %wu\ntable: %wu\nbsgs: %wu\ncrt: %wu\nprecomp1: %wu\nprecomp100: %wu\n\n",
-                        l0, l1, l2, l3, l4, l5);
+                flint_printf("once: %wu\ntable: %wu\nbsgs: %wu\ncrt: %wu\nprecomp1: %wu\nprecomp100: %wu\nrho: %wu\n",
+                        l0, l1, l2, l3, l4, l5, l6);
                 flint_abort();
             }
         }
         dlog_table_clear(table);
         dlog_bsgs_clear(bsgs);
         dlog_crt_clear(crt);
+        dlog_rho_clear(rho);
         dlog_precomp_clear(pre1);
         dlog_precomp_clear(pre100);
     }
diff --git a/src/dlog/test/t-modpe.c b/src/dlog/test/t-modpe.c
index 7b26ef9836..ad272bf057 100644
--- a/src/dlog/test/t-modpe.c
+++ b/src/dlog/test/t-modpe.c
@@ -23,7 +23,7 @@ TEST_FUNCTION_START(dlog_modpe, state)
 {
     slong iter;
 
-    for (iter = 0; iter < 1000; iter++)
+    for (iter = 0; iter < 100 * flint_test_multiplier(); iter++)
     {
         ulong p, e, pe, a;
 
diff --git a/src/dlog/test/t-vec.c b/src/dlog/test/t-vec.c
index 462725c7bd..3a70437170 100644
--- a/src/dlog/test/t-vec.c
+++ b/src/dlog/test/t-vec.c
@@ -61,7 +61,7 @@ TEST_FUNCTION_START(dlog_vec, state)
             ref = flint_malloc(nv * sizeof(ulong));
             v = flint_malloc(nv * sizeof(ulong));
 
-            for (iter = 0; iter < 10; iter++)
+            for (iter = 0; iter < FLINT_MAX(2, flint_test_multiplier()); iter++)
             {
 
                 int k;